San Diego Agency Seeks Energy Storage Project Proposals

The San Diego County Water Authority has issued a request for proposals (RFP) for a potential joint energy storage project with the City of San Diego.

According to the public agency, the project could lessen upward pressure on water rates and also increase opportunities for renewable energy penetration throughout the region by leveraging existing infrastructure at San Vicente Reservoir.

The facility would consist of a closed-loop interconnection and pumping system between the existing San Vicente Reservoir (which is owned by the City of San Diego) near Lakeside and a new, smaller reservoir located uphill.

Used during offpeak energy-use periods, it would pump water uphill to the new upper reservoir to create a bank of stored hydroelectric energy (up to 500 MW). That energy would be released to the lower reservoir by gravity at times when other renewable energy supplies, such as solar, are unavailable and when energy demand and electricity costs are higher.

The water authority says the energy storage project would support grid operations that are essential to integrating large new supplies of other renewables into the California and Western power grids – notably, wind and solar. It also would make it easier to quickly ramp up or down energy generation as needed.

“This potential project is an exciting and innovative opportunity to optimize our water facilities to benefit our ratepayers while helping the region as a whole meet its energy needs,” comments Mark Muir, chair of the water authority’s board of directors. “The competitive bidding process will help ensure this potential project delivers maximum value.”

The RFP calls for any interested parties to provide details of their full-service teams qualified to perform all activities to deliver an operational project. The water authority expects to evaluate received proposals this fall and to seek approval from the board to begin negotiations with a potential full-service team by the end of this year.

In March, the board authorized the agency to begin seeking detailed proposals for a potential energy storage facility at the reservoir after a successful gauge of interest in the potential project earlier in the year. That solicitation drew responses from 18 qualified entities, the agency says.

Proposals are due to the water authority by 2 p.m. PT on Sept. 12. Questions regarding the request must be emailed no later than 2 p.m. PT on Aug. 29. Submittals of both proposals and technical questions regarding the request should be directed to Jennifer Graffam at jgraffam@sdcwa.org.